(170a) The Role of Carbon Dioxide As a Solvent for Greener Biodiesel Production over a Heterogeneous Catalyst

Authors: 
Soh, L., Lafayette College
Zimmerman, J., Yale University
Chen, C. C., Industrial Technology Research Institute

Within the field of alternative energies, fuels produced from biological feedstocks have great potential to replace petroleum-based products. In order to sustainably produce fuels and materials, biorefineries must be designed for and operated with sustainable processes.  Compressed carbon dioxide – subcritical, supercritical, and CO2 expanded liquids – can potentially be used in a biorefinery as a green solvent.  Key processes that may be improved via the use of CO2 are extraction (including fractionation and refinement) and reaction.  In this presentation, supercritical CO2 (scCO2) is shown to be an effective solvent for the selective conversion of lipids into biodiesel in combination with a heterogeneous catalyst. Successful transesterification of triglycerides into fatty acid methyl esters is demonstrated via a CO2-expanded liquid phase.  The role of CO2 in reaction moderation is explored via kinetics with potential implications for selectivity and system optimization.  While pitfalls do exist for the application of compressed CO2 in commercial production, this versatile compound holds great promise for utilization as a green solvent in a biorefinery setting.